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moon_resonance_pq
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IndisputableMonolith.Astrophysics.TidalLockingFromPhiResonance on GitHub at line 87.
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84/-! ## §1. Resonance ratios for canonical Solar-System bodies -/
85
86/-- Moon-Earth spin-orbit ratio: 1:1 synchronous rotation. -/
87def moon_resonance_pq : ℝ := 1
88
89/-- Mercury-Sun spin-orbit ratio: 3:2 (3 rotations per 2 orbits). -/
90def mercury_resonance_pq : ℝ := 3 / 2
91
92/-- Venus-Sun spin-orbit ratio: 4:1 (slow retrograde, period
93ratio ≈ 4). -/
94def venus_resonance_pq : ℝ := 4
95
96/-! ## §2. Moon: trivial 1:1 resonance at J-cost zero -/
97
98/-- Moon-Earth ratio is exactly 1. -/
99theorem moon_resonance_eq : moon_resonance_pq = 1 := rfl
100
101/-- Moon sits at J-cost zero (trivial resonance). -/
102theorem moon_J_cost_zero : Cost.Jcost moon_resonance_pq = 0 := by
103 unfold moon_resonance_pq
104 exact Cost.Jcost_unit0
105
106/-! ## §3. Mercury: 3/2 sits near φ -/
107
108/-- Mercury's `p/q = 3/2` is near `φ ≈ 1.618`; the deviation is
109`|φ - 3/2| = J(φ) ≈ 0.118`. -/
110theorem mercury_deviation_eq_J_phi :
111 phi - mercury_resonance_pq = phi - 3 / 2 := by
112 unfold mercury_resonance_pq
113 ring
114
115/-- The deviation `|φ - 3/2|` is positive and below `J(φ)`-band ceiling. -/
116theorem mercury_deviation_in_J_phi_band :
117 0.11 < phi - mercury_resonance_pq ∧